Systems in the body

• Multi-cellular organisms


  11 systems that work together
• The 11 systems


  • Respiratory system
  • Reproductive system
  • Circulatory/cardiovascular system
  • Digestive system
  • Musculoskeletal
  • Excretory system
  • Nervous system
  • Endocrine system
  • Lymphatic system
  • Immune system
  • Integumentary system (also called the exocrine system)
• Musculoskeletal system


  • Provides framework and protection
  • Provides support and enables movement
• Musculoskeletal system processes


  1. Contraction and relaxation of muscles

  2. Movement (locomotion)
• Musculoskeletal system components


  • Bones
  • Muscles
  • Ligaments
  • Tendons
  • Cartilage
• Bones


  • Provide shape
  • Protect internal organs
  • Site for muscle attachment
  • Produce red blood cells
• Muscles


  • 3 types: smooth, skeletal, cardiac muscle
  • Made up of muscle fibres (cells) with dark and light bands
  • Contract/relax to allow movement
• Ligaments


  • Connect bone to bone
  • Holds bones in place at the joints
  • Prevents dislocation during movement
• Tendons


  • Attach the muscles to the bone
  • Absorb impact from muscle movement
• Cartilage


  • Covers and protects the ends of bones at the moveable joints
  • Acts as a shock absorber in joints
• Excretion


  Removal of CELLULAR or METABOLIC waste
• Excretory organs


  • Skin
  • Lungs
  • Kidneys
  • Liver
• Urinary system


  • Filters waste products from the blood
  • Regulates body fluids
• Urinary system components


  • Kidneys
  • Ureters
  • Bladder
  • Urethra
• Kidneys


  • 2 bean shaped structures on either side of the vertebrae
  • Filters waste products from the blood
  • Produce urine to be removed
  • Urine is made up of water, urea, salts, creatinine and other wastes
  • Regulates water levels (osmoregulation)
• Ureters


  Tube carrying urine made in the kidneys to the bladder
• Bladder


  • Muscular sac that stores urine
  • Muscles are responsible for releasing or holding urine
• Urethra


  • Carries urine from the bladder to the outside
  • Male urethra is much longer than females
• Urination process


  1. Bladder fills with urine and expands/stretches

  2. Stretch receptors send signals to the brain

  3. Brain determines urgency - hold in or release urine

  4. Bladder muscle contracts and sphincter relaxes to release urine
• Urinary system processes


  1. Filtration

  2. Absorption

  3. Diffusion

  4. Excretion
• Nervous system


  • Receives and processes information about the world outside in order to react, communicate, and keep the body healthy and safe
• Nervous system components


  • Central Nervous system (Brain & Spinal cord)
  • Peripheral Nervous system (Nerves)
  • Sense organs
• Central Nervous System


  • Brain - Controls all functions in the body, Interprets information and stores them into memory
  • Spinal Cord - Bundle of nerves running down in the vertebrae, Conducts impulses to and from the brain, Can work independently without the brain
• Peripheral Nervous System


  • Nerves - Transmit signals (impulses) throughout the body
  • Sense Organs - 5 sense organs received information from the outside environment to send to the brain for interpretation
• Nervous system processes


  1. Sensing with sense organs (Tasting, hearing, seeing, feeling, smelling)

  2. Sending and receiving impulses (Received by sense organs then transmitted to the brain for interpretation)

  3. Regulating Temperature (Brain and skin regulates body temperature, Skin produces sweat to cool the body down when it is hot)